A skiboot is a heavy duty piece of footwear which must fulfill various rather stringent requirements. First of all it must snugly encase the foot and lower ankle of the wearer so as to prevent the most common type of skiing injury; a sprained or broken ankle or twisted ankle joint. At the same time it must give the user sufficient freedom of motion that he or she can maneuver while skiing. Finally a skiboot must be relatively easy to put on and remove as the boot is normally not comfortable for walking and the user is frequently wearing heavy gloves or mittens when putting it on or taking it off.
A common type of skiboot comprises synthetic-resin upper whose top is open from immediately adjacent the toes all the way up to the collar of the boot. A row of boot closures is provided along this opening which serve both to close the shoe part over the foot and to tighten the ankle part around the ankle.
Such a skiboot has the considerable disadvantage that the closures invariably exert a backward force on the foot of the wearer. Thus if tightened the foot of the wearer is pushed to the back of the boot. Thus the skier typically tightens the closures on top of the foot considerably more than the closures at the front of the ankle in order to hold the foot down in the middle of the boot. This fastening method is relatively uncomfortable and does not assure a proper positioning of the foot within the boot.